1. Field
Aspects of embodiments of the present invention relate to a display device and a driving method of the display device.
2. Description of Related Art
Display devices, such as liquid crystal displays (LCDs) and organic light emitting diode displays, generally each include a display panel and a driving device for driving the display panel. The display panel includes a plurality of signal lines and a plurality of pixels connected thereto and arranged substantially in a matrix form. The signal lines include a plurality of gate lines transferring gate signals and a plurality of data lines transferring data voltages, or the like. Each pixel may include at least one switching element connected to a corresponding gate line and a corresponding data line, at least one pixel electrode connected thereto, and an opposing electrode facing the pixel electrode and receiving a common voltage.
The switching element may include at least one thin film transistor, and is turned on or off according to a gate signal transmitted by the gate line to selectively transmit a data voltage corresponding to an image signal transmitted by the data line to the pixel electrode. Each pixel receives the data voltage, corresponding to desired luminance, through the switching element. The data voltage supplied to each pixel is applied as a corresponding pixel voltage to the pixel electrode and the pixel displays the desired luminance as a gray level corresponding to a difference between the pixel voltage and a common voltage supplied to the opposing electrode.
A driving device of the display device includes a graphics controller, a driver, and a signal controller for controlling the driver. The graphics controller transmits input image data for an image to be displayed to the signal controller. The input image data has luminance information for the respective pixels, and each luminance is represented by a predetermined number. The signal controller generates control signals for driving the display panel and transmits the control signals and the image data to the driver. The driver includes a gate driver for generating gate signals and a data driver for generating data voltages.
In order to display images by pixels with desired luminance at the right time, the pixels need to charge for a sufficient period of time, and gate doubling may be used to accomplish this. For each row of pixels, gate doubling outputs compressed image data of two or more rows, and at least doubles the frame rate by simultaneously driving a plurality of gate lines for at least part of the time. As such, gate doubling allows continuous input of output image data for the same input image data to the display panel for multiple gate lines concurrently to increase a response speed of the pixels and reduce crosstalk between neighboring frames. However, gate doubling outputs compressed image data, so vertical resolution may deteriorate.
Gate doubling driving may be usable for displaying 3D images or multi-view images as well as 2D images. In general, with 3D image display technology, a 3D effect of an object is expressed by using binocular parallax, which is the largest factor with regard to recognizing the 3D effect at short range. With binocular parallax, when different 2D images are displayed concurrently to the left eye and the right eye, respectively, and the image displayed to and received by the left eye (hereinafter referred to as the “left eye image”) and the image displayed to and received by the right eye (hereinafter referred to as the “right eye image”) are transmitted from the optic nerves of the left and right eyes to the brain, the left eye image and the right eye image are fused in the brain and recognized as a 3D image having 3D effects such as depth.
A 3D image display device capable of displaying 3D images uses binocular parallax. 3D image display devices include stereoscopic 3D image display devices using glasses (such as shutter glasses, polarized glasses, or the like) to generate the 3D effect, and autostereoscopic 3D image display devices, which use an optical system (such as a lenticular lens, a parallax barrier, or the like) in the display device to generate the 3D effect without using glasses.
When the stereoscopic 3D image display devices using shutter glasses display 3D images, frames of left-eye images and right-eye images are separated from each other and alternately displayed to decrease crosstalk between neighboring frames intended for different eyes. Therefore, when such a display panel is driven according to the gate doubling driving scheme, the same image data may be input to the display panel with a faster frame rate (thereby increasing the pixel's response speed) and while reducing the crosstalk between neighboring frames. These are also applicable to multi-view display devices for displaying different images to an observer as well as to other 3D image display devices.
With gate doubling driving, vertical resolution of output image data output to the display panel may be less than or equal to half the vertical resolution of output image data that do not undergo gate doubling. As such, shapes or edges having curved lines (such as a circle) or oblique angles may not appear'smooth but rather like saw teeth, which is called aliasing. Aliasing usually worsens resolution of images and deteriorates image quality.
The above information disclosed in this Background section is for enhancement of understanding of the background of the present invention and therefore it may contain information that does not form the prior art already known in this country to a person of ordinary skill in the art.